The defense attorneys for Jerry Sandusky had been intent on putting the former Penn State coach accused of child sex abuse on the stand to defend himself, but changed their minds today because they felt they had already raised significant doubts about the prosecution's case, ABC News learned exclusively today.

Earlier this week, sources said, the defense team was convinced they would have to put Sandusky on the stand to prevent him from being convicted of the 51 counts against him and possibly spending the rest of his life in jail.

Sources said that the defense team made their decision after Tuesday's testimony in which the two lead investigators in the case told the court that they had not shared specific allegations of sex abuse with potential victims during interviews, but were shown to have done just that during an accidentally-recorded interview played for the jury.

One investigator was heard telling the man known as Victim 4 that others had already come forward claiming that Sandusky forced them to perform oral sex and raped them, even though Victim 4 had not said that Sandusky sexually abused him.

The defense has claimed that the investigation was "tainted" by eager state troopers who encouraged the alleged victims to claim they were abused.

Defense attorneys Joseph Amendola and Karl Rominger, along with Sandusky, made their decision today just moments before they would have had to call Sandusky to the stand. Sandusky was then brought into Judge John Cleland's chambers, where Cleland asked Sandusky if he knew that he had the right to testify in his defense and was giving up that right by choice. Sandusky told the judge he was aware, sources said.

The frantic decision-making took place during 45 minutes of closed-door meetings in conference rooms off the courtroom, ending with Amendola telling the court that the defense had chosen to rest its case.

Both sides will offer their closing arguments to the jury on Thursday before the case is handed over to the jury of seven women and five men for deliberations.

It would have been a gamble to put Sandusky on the stand because it would then open him up to withering cross examination by the prosecutor.

Sandusky, 68, is charged with 51 counts of sex abuse against 10 boys. If convicted he could be sentenced to life in prison.

People in Bellefonte, Pa., lined up outside of the Centre County courthouse as early as 3:30 a.m. today to get one of the extra folding chairs that have been set up in the back of the court in hopes that former Penn State football coach Jerry Sandusky will take the stand on the final day of testimony in his child sex abuse trial.

"I've been following it because I'm interested in the effects on Penn State," said Jillian Damus, 17, a high school student from State College. "Of course I want to see Jerry Sandusky testify. He hasn't done a very good job so far."

The defense concluded their case this morning following a day of strong testimony in their favor in which the accounts of two lead investigators were called into question and the testimony of Sandusky's wife was unwavering in its denial of sexual abuse.

"The community needs to know what happened," said Gerneylee Carter, 58, of Bellefonte. "There was a major breach of trust, and it's not going to be restored until we know what happened. I was here all last week and I'm usually here at 6:30 a.m."

Carter and dozens of other members of the public, from towns as close as Bellefonte and as far away as Pittsburgh and San Francisco and Florida filed into the courtroom ahead of an early 8:30 a.m. start today.

Sandusky's lawyers made their final efforts to cast doubt on the investigation, which they have claimed was tainted by state troopers by leading alleged victims into making accusations.

David Hilton told the jury today that he spent five years with Sandusky and that nothing inappropriate ever occurred.

But Hilton said he was interviewed by police three times and told he could be charged with a felony if he didn't tell the truth.

"The second and third times they wanted me to say something that wasn't true. They would ask questions in different ways to see if I slipped up. They said if I was lying then I could get in trouble with like a felony or I could get in trouble somehow," Hilton said.

The defense also went after the credibility of key witness Mike McQueary again today, calling to the stand McQueary's close family friend Dr. John Dranov.

McQueary was an assistant coach who testified that he interrupted Sandusky raping a boy in the school's showers.

Dranov, who was called to the McQueary home after McQueary said told his father what he saw, told the court that McQueary did not say that he saw sex between Sandusky and the boy.

"(He) described that he heard sexual sounds. I said, 'Mike, what do you mean?' and he said 'sexual sounds, you know what I mean.' I said, 'No, Mike, what do you mean?' And he got upset, so I left that. He said he looked at the shower and a young boy looked around and he made eye contact with the boy, and I asked whether boy looked upset or frightened , and he said no."

McQueary testified on behalf of the prosecution last week that he did not see a sexual act but, because of the close proximity of Sandusky to the boy and the slapping sounds, believed he walked in on anal rape.

The defense has tried to cast doubt on McQueary as a witness, showing that his testimony to the grand jury that he witnessed rape was different from his testimony and statements on other occasions.

McQueary also testified last Tuesday that after the incident, he avoided Sandusky in the locker room and outside of Penn State, and never played in another charity golf tournament held by Sandusky's charity The Second Mile.

A Second Mile staff member appeared in court today with a letter from the Second Mile addressed to McQueary, thanking him for his participation in a 2003 golf outing. His name was also on a list of players from the fall 2001 golf outing, which took place at least six months after the incident in the locker room.